atcomsystems.ca/forum Forums Other TDM Phone Systems Antique Telephones Re-wiring a 1987 2500 ITT/Cortelco

Hi everyone, a little back-story: I bought a perfectly functional Cherry Red 2500 Set at a HAM Radio swap meet several years ago.

I salvaged the handset off it for re-wiring to a cellphone, that worked great.

I originally marked where the handset connections went but in the process of reconnecting them I managed to disconnect some other wires like a fool.

I now want to put the phone back in working order since I now need a land-line and this thing is positively gorgeous.

I've located the schematics for the 2500D and everything is peachy except I've got no terminals marked S or T, instead I've got E1 and E2.

Also on the dial I've got 9 wires including a brown wire attached to a black plastic sheet surrounding the digits, some of the colors here do not match the schematics.

I want to tear the thing down completely clean it, and put everything back in it's intended place, is this a terrible idea or what?

I'm happy to post some pictures if it would help resolve my issue.

Thanks everyone!!

Terminals S, T, E1 and E2 are just blind tie points to allow you to connect two leads together.

The brown lead attached to the black plastic sheet is just a static discharge mat. This wire should connect to terminal L1.

Pictures will be great, so if you can post back with them, we'll have you talking on that thing in no time.

Hey thanks a ton Ed, that info was probably all I need, but here's the pics posted in a public Flickr photoset .

I'll review my schematic with the info you just mentioned and see if it makes more sense now.

Let's try this. I'm doing this from memory, but many connections are not polarity-sensitive so it should not matter. (Note: Each terminal will accept up to four spade-tipped wires, so you will have multiple connections on the same terminal):

Line cord:

Red to terminal L2
Green to terminal L1
Yellow to terminal G
Black insulated and stored

Ringer:

Red to terminal L2
Black to terminal L1
Slate to terminal A
Slate/red to terminal K

Dial:

Brown (static shield) to terminal L1
Orange/black to terminal C
Black to terminal RR
Blue to terminal B
Red to terminal E1
White to terminal E2
Green to terminal F
White/blue to terminal R
Red/green to terminal R

Handset:

Red to terminal E1
Black to terminal B
White to terminal E2
Other white to terminal GN

Switch Hook:

Slate to terminal L2
Slate/yellow to terminal L2
Slate/green to terminal L1
Slate/white to terminal F
Slate/black to terminal GN
Slate/red to terminal E2
Slate/brown to terminal L2 on back of dial.

Ok Ed, I re-wired based on your instructions and I'm able to dial out and ring-in but there's no sound on the handset.

I head no dial-tone but very faint dialing tones when I pressed buttons on the dial.

Tried swapping the whites, no-go.

My colors on the dial-pad do not match your list, here's what I've got:
Brown (from static discharge mat)
Red-Green
Blue
Green
Orange-Black
Black
Red
White
Grey-Brown

I know the handset itself is functional because the reason it was removed was to adapt it to a cellphone. Before I took apart the cellphone adapter to restore the phone I tested it one last time.

Any more tips?

Move the wires that are on terminal E2 to terminal GN. Move the other white handset lead from terminal GN to terminal R. You should end up with one white handset wire on terminal GN and the other on terminal R. Let me know how you make out.

Ok Ed, with your instructions I am able to hear but the handset mic is no-go.

So close, what am I missing!?

Try moving the red handset lead from terminal E1 to terminal R just to see if it works. Check back and let us know.

Same result with handset red lead on R

OK, let's try one more thing:

Disconnect the blue dial lead from terminal B. This should leave you with only the black handset lead on terminal B. Insulate the blue wire now for testing purposes. If that doesn't work, then you probably have a bad component. Fortunately, these parts are cheap and easy to come by. Check back and let us know.